Teacup cats are fascinatingly delicate creatures.
Humans like the appearance of "jewel like" animals and these sweet, very small cats are certainly that.

Smaller than usual cats occur for several reasons - some genetic, some hormonal and some environmental.

What are teacup cats?

Teacup cats are simply small miniature cats (meaning a size smaller than the category of cat called "miniature cats"). Miniature cats are usually about one third to one half the size of normal size cats of the same breed. As a guideline teacup Persian females weigh 2-4 lbs while the males are 3-6 lbs.

At least one cattery sub-classifies by referring to "Palm Sized Pocket Persians" as well. Female palm sized weigh 3.5lbs or less and males 4lbs or less.

They are normally less than 9 inches tall or less when mature. Miniature kittens are more vulnerable than normal sized kittens. Being miniature poses health problems to pregnant cats so the breeding females must be 4-8 lbs in weight and breeding males are 4-10 lbs. It seems that they are friendly (to humans and dogs!) cats.

i belive there is such thing, because they do have tea cup dogs, because i have one and a tea cup kitten there could be such thing because they could have a defect or they could just be that small... but they are so cute.. =D

I actually had one. The cat was caused by an accidental long line of inbreeding between brother and sister cats. You would think cats outside would find some other cat other than their sibling. As I said the inbreeding was entirely accidental, but pygmy cats were produced about 1/4 of the size of a normal cat. I guess you can call it a teacup cat if you like. Many people lay different names on different things. Some people lay nicknames on animals or other things if they don't know the real name. That is probably how the name pygmi cat turned up. Just to clarigy things though, I don't like inbreeding. Imbreeding causes major major defects and health problems in the cats too.

Heyyy... That's my cat!
To answer all your questions about pygmy cats, there ARE actually what people call "teacup" breeds. What it actually is is a form of dwarfism know as primordial dwarfism.
It causes severe growth retardation in the cats and several severe health problems.

My cat, Melvin, is one of these cats. He is currently 9 months old and only 6 pounds. This may seem like a normal cat weight but the problem is is that he is actually OVERWEIGHT and the vet has told us that once he hits 1 years old, he will most likely need to diet. His practical weight for his body size is around 3 to 4 pounds.

Thankfully, he's all fluff, so he looks a bit bigger than he actually is.

Here's some videos of him nowadays:

He actually has his own website, as well: http://www.mouchois.com

Some of the health problems of cats with this disease are seizures, neurological disorders that can sometimes cause blindness, heart murmurs, enlarged heart, bone deformities (misshapen jaw, bowed legs, etc), and I think a few more, but I can't remember them all. Melvin has all of these. He's blind in one eye, has seizures, has heart murmurs, he still has not gotten his adult teeth, his heart is a big larger than should be for his size, he was born without testicles (or they are extremely tiny), he has bowed back legs and a soft spot on the top of his head.
Beyond all of these health problems, he is a genuinely healthy cat and well cared for (spoiled to death). I'm currently NOT putting him on the diet due to the vet's advice to keep him well nourished due to the fact that this form of dwarfism is rather rare. As soon as his bones are completely formed and that soft spot goes away (which we aren't sure if it will or not), we are feeding him kitten diet, raw food, and wet food (to keep UTIs down). This adds on the pounds, but keeps him from needing mass amounts of supplements.